§ 130.50 Criminal sexual act in the first degree. A  person is guilty of criminal sexual act in the first degree when he  or she engages in oral  sexual  conduct  or  anal  sexual  conduct  with  another person: 1. By forcible compulsion; or 2. Who is incapable of consent by reason of being physically helpless;  or 3. Who is less than eleven years old; or 4. Who is less than thirteen years old and the actor is eighteen years  old or more. Criminal sexual act in the first degree is a class B felony.